It really sucks when relationships end, especially ones as long as these. I feel for you. It is a big blow, and you are grievingg a relatively signifiant loss. There are also a lot of fears that will surface now, and you are forced to evaluate your standing as a person, who is suddenly (somewhat) alone in the world. This can be some heavy shit. In my opinion, there are some healthy ways of processing it all and working through the messy feelings, and then there are some not so healthy ways of doing it.
To be honest SCONNIE: it seems like this has hit you hard, and you're a bit of a mess. That's okay, but it will pay to be clever about all of this now.
I'd cancel the date personally. A few days ago you cancelled a date because you thought you were nowhere near ready, and you were right - nothing has changed in a few days. You are still reeling from all of this, and you are desperately hoping that your boyfriend comes back. You have not processed all of this yet. This break up has been a shock to you, and you're scared of the future right now. I think now is a really good time for you to take a solid break from dating, and focus completely on yourself.
You said that you'd started doing some reading on Buddhism, had been working out and picked up your guitar. This is the sort of thing you need right now. Bringing some guy into the picture isn't wise at a time when you're already feeling rejected, abandoned and vulnerable. Find yourself properly again, and work on your self-esteem - getting dumped by the love of your life would be a massive blow to anyone's ego. You also mentioned abandonment and control issues that you wanted to work on - I definitely think you could benefit from working with a therapist over this. Sure, you may be able to work through it just fine on your own, but it's smart to use a therapist to ensure that it happens as quickly as possible.
I think it's a good idea to work on your independence at this point. I'd try to become comfortable being alone before even consider entering into another relationship.
Breakups suck, and they're damaging. The way you feel now is normal, and it will pass. Reach out to your family and friends, and re-establish those support networks - you will start feeling better soon.
And most definitely cut all contact with your ex immediately - it will only bring you pain. You have nothing to gain from it. You don't want to know about his dates, or anything about his life. If you have mutual friends, advise them of this. His life is his life now, and yours is yours. Focus on yours. You need to have zero contact in order to move on.
I hope that made sense - I'm pretty stoned and I just realised how long it is so cbf proof reading. lol.
But yeah, good luck - you'll feel better soon enough.
. It's a struggle for sure, but i'm just hitting the gym and working on my car heaps, trying to focus on myself and my hobbies. Although i'm fairly confused about how to get back into the dating world, I figure it'll happen naturally once i'm ready, i'm sure the same will go for you 
